Hot-air heater.



H. S WILLIAMS.

HOT AIRYHEATER.

APPLICATION FILED OCT. 30. 19:2.

Patented Jan. 25, 1916.

nnrrnn snares PATENT @FJFIQE.

HARRY S. WILLIAMS, OF DETROIT, MICHIGAN, .{ISSIGNOR T0 PETER SMITH HEATER COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

HOT-AIR HEATER.

Specification Bf Letters Patent.

Patented Jan. 25, 11916.

Application filed October 30, 1912. Serial No. 728,653.

tain new and useful Improvements in Hot- Air Heaters, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relatesto hot air heaters of that type in which the circulation of the air over the heating surface and to the point of distribution is mechanically propelled by a fan or equivalent device, the construction being particularly adapted for car heaters. f With heaters of this type it is usual to force air downward through the heater, or in opposition to the natural circulation by gravity, in order that it mayabe conducted through conduits near the floor of the car. If, however, the fan is stopped I as, for instance, where the trolley is disconnected, the air will not circulate but will be trapped in the heating chamber.

It is the object of the present invention to provide automatic means for establishing a and outer-icasings'B and C, and-the outlet gravity air circulation whenever the fan is inoperative, and to this end the invention consists in the construction as hereinafter set forth, described and claimed.'

In the drawings: Figure l'is a-vertical central section through a heater provided with my improvement, showing the parts in normal position where the fan is in-o'pera. tion. Fig. 2 is a similar view, showing the automatic adjustment for establishing gravity circulation. Fig. 3 is a cross section of the heater taken on the line y-y of Fig. 1, and Fig.4 is a cross section'taken on the line of Fig. 1. M

A is a'stove of any-suitable construction and B is a surrounding casing therefor.

C designates an outer casing. At the base of the stove is an air inlet chamber D, said;

chamber being provided with inlet openings D and outlet openings D communicating with the space between the inner casing B and the outer-casing C. A motor driven, fan G is mounted on the top of the casing C. "The inlet to the casing of the fan G communicates with the space between therinner from the casing of the fan is connected by a conduit H with the top of the chamber I Within the inner casing B.

J is the heat distributing conduit connectmg with the lower end of the chamber Lthe arrangement being such that when the fan G is in operation, air will be drawn from. the chamber D upward through the space between the inner and outer casings B and C and then forced downwardly through the inner chamber I to the distributing conduit.

In the particular embodiment of the invention illustrated in the drawings, an intermediate casing E is provided forming with the inner casing B an intermediate chamber E in direct communication through the openings D with the air inlet chamber D, andalsogin communication with the inlet of the fan'casing by a conduit F. In this particular construction, when the motor is operated to drive the fan G the air is drawn through the lower openings D in the chainber D upwardly into'the chamber E, being heated in its upward travel, and the air thence passes through the conduit F to the inlet of the casing of the fan G, and is forced through the fancasing downwardly through the inner chamber I to the distributing conduit J.

To permit of a "-ravity circulation when the fan brris out 0 operation means is provided for affording a communication be tween the inner chamber I and the atmosphere. For this purpose openings K and L are provided respectively in the conduit H and in the casing C, and dampers M and N are employed to control. said openings. which are arranged in horizontal alinemen't with each other. The dampers .\I and N, which are in the form of plates and are of the outer casing C and to the wall of thecondmt H respectively, are suitably connect- .ed together so that the opening of one will gravity, and the damper isso hinged that 'pivotally connected at one end to the wall in its open position it will obsti act the conduit H.

P designates a counterweight connected with the damper N. Thus, with the dampers M and N in open position as indicated in -Fig. 2 of the drawings, whenever air is forced through the conduit H by the operation of the fan, the pressure of air against the damper M will force the same to its closed position, and through the connecting rod 0 will simultaneously close the damper N against the action of thecountcrweight 1.

This position of the parts, as shown in Fig. 1 of the drawings, will be maintained as long as the air is propelled Jay the fan, but upon the stopping of the circulation by the fan, the dampers M and N will be automatically opened by the counterweight ,P,

and a gravity circulation permitted.

from the. chamber I passing outward through the aperture K and registering aperture L.

It will be noted that the present invention provides means for propelling air through the casing the air propelled acting upon one of a plurality of connected members and controls an inlet to the casing. The

arrangement is such that the action of the blast will immediately move both members simultaneously to close the openings.

What I claim as my invention is:

1; Ihe combination with a hot air heater having an outer and an inner heating chamber, of a mechanically-operated fan for drawing air from said outer chamber and forcing it downwardly into said inner chamber, a conduit passing) through said outer chamber and connecting with the upper end of said inner chamber, through which the airis forced downward, and a pair of con-- nected dampers controlling registering openings in said conduit and outer casing, and adapted to automatically open to provide an exit for the heated air, the inner damper when open obstructing the path of air through said conduit, whereby said dampers will be closed when the air'is mechanically propelled.

2. The combination with ahot air heater having inner and outer heating chambers,

of' a fan for drawing air from the outer chamber and forcing-it downwardly through the-inner chamber, a conduit through which the air is propelled, passing through said mdsphere.

outer chamber and connecting with the upper end of said inner chamber, a damper in said conduit controlling a lateral opening therein, and in its open position obstructing said conduit, a damper controlling an opening in the outer casing and connectedwith the firstmentioned damper to operate simultaneously therewith, and means for automatically opening said dampers, said means adapted to be overcome by the force of air against the inner damper when the fan is in operation.

A heater of the character specified comprising an inner casing, a heating element arranged therein, an outer casing, means for causing the air to circulate through the outer casing inwardly into and through the inner casing, there being a hot air outlet from the inner casing, said inner casing and outer casing having openings whereby communication may be established between the inner casing and the atmosphere, a plurality of connected damper members operated simultaneously by the blast of an from said am circulating means to cut off commumcatlon between the inner casing and the atmosphere,

and a weight acting simultaneously upon both of said damper members when the circulating means is idle to establish communication between said inner casing and the at- 4. A heater including an inner casing; a heat producing element arranged in said casing, an outer casing surrounding the inner casing, the outer casing and inner casing each having a natural draft egress opening, vertically swinging members, a connection between the members whereby the same move simultaneously, one of said members forming a closure for the egress opening in the outer casing and the other forming a closure for the egress opening in the inner into the upper part of the inner casing and casing, afan for forcibly introducing air downwardly through the same, the inner casing being provided at its bottom with a hot air outlet, the blast from said fan acting to operate the connected members whereby the same close the egress openings in the.

outer'casing and inner casing, and means acting upon said members when the fan is idle to simultaneously open the egress opene ings to allow for anatural draft circulation. 5, A heater including an outer casing and .an inner casing, a mechanically operated fan for forcing air into and downwardly through said inner casing, the inner casing and outer casing each being formed with a natural draft egress opening, a heating element arranged w1th1n the inner casing, the inner casing at its base being provided with an outlet for the heated air which is forced downwardly through the same by said fan, a conduit passing through the outer casing and communicating with the inner casing, the blast from the fan passing through said coning of the outer casing, a Weight acting simultaneously upon both of said members when the fan is idle to establish communication through the egress openings between the outer casing and the atmosphere, the first mentioned damper member when in open position obstructing the conduit passage whereby the air is deflected through the egress opening of the inner casing.

6. A heater including an inner casing, a heating element therein, an outer casing surrounding the inner casing, air propelling means for causing air to circulate through the inner casing, there being communicating openings, one of said openings being formed in the outer casing and the other communicating with the inner casing, said openings serving to vent the inner casing through the outer casing to the external-atmosphere, a damper controlling the opening communicating with the inner casing and automati cally closed by the blast of air from the air propelling means, and means for automatically opening said damper when the air propelling means is out of operation.

7. A heater including an inner casing, a heating element therein, an outer casing surrounding the inner casing, air propelling means having a duct leading therefrom through the outer casing and communicating with the inner casing adjacent the top thereof, a vent in the duct for communicat- .ing with the external atmosphere whereby the inner casing may be vented through the duct to the external atmosphere, a damper controlling said vent and automatically closed by the blast of air passing through said duct, and means for automatically opening said damper when the air propelling means is out of operation.

In testimony whereof I afiixmy signature in presence of two Witnesses.

HARRY S. WILLIAMS. Witnesses:

WM. J. BELKNAP, JAMES P. BARRY. 

